Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

A double-blind, controlled clinical trial in 1,955 evaluable women compared the efficacy and safety of levonorgestrel tablets (one 0.75 mg tablet of levonorgestrel taken within 72 hours of unprotected intercourse, and one tablet taken 12 hours later) to the Yuzpe regimen (two tablets each containing 0.25 mg levonorgestrel and 0.05 mg ethinyl estradiol, taken within 72 hours of intercourse, and two tablets taken 12 hours later).

The most common adverse events ( > 10%) in the clinical trial for women receiving levonorgestrel tablets included menstrual changes (26%), nausea (23%), abdominal pain (18%), fatigue (17%), headache (17%), dizziness (11%), and breast tenderness (11%). Table 1 lists those adverse events that were reported in ≥ 5% of levonorgestrel tablets users.

Table 1: Adverse Events in ≥ 5% of Women, by % Frequency

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Next Choice™. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Gastrointestinal Disorders

Abdominal Pain, Nausea, Vomiting

General Disorders and Administration Site Conditions

Fatigue

Nervous System Disorders

Dizziness, Headache

Reproductive System and Breast Disorders

Dysmenorrhea, Irregular Menstruation, Oligomenorrhea, Pelvic Pain

Read the Next Choice (levonorgestrel tablets) Side Effects Center for a complete guide to possible side effects »

Drugs or herbal products that induce enzymes, including CYP3A4, that metabolize progestins may decrease the plasma concentrations of progestins, and may decrease the effectiveness of progestin-only pills. Some drugs or herbal products that may decrease the effectiveness of progestin-only pills include:

• barbiturates
• bosentan
• carbamazepine
• felbamate
• griseofulvin
• oxcarbazepine
• phenytoin
• rifampin
• St. John's wort
• topiramate

Significant changes (increase or decrease) in the plasma levels of the progestin have been noted in some cases of coadministration with HIV protease inhibitors or with non-nucleoside reverse transcriptase inhibitors.

Consult the labeling of all concurrently used drugs to obtain further information about interactions with progestin-only pills or the potential for enzyme alterations.

Drug Abuse And Dependence

Levonorgestrel is not a controlled substance. There is no information about dependence associated with the use of Next Choice™.

Last reviewed on RxList: 7/19/2011
This monograph has been modified to include the generic and brand name in many instances.